Well, there's use and then there's use. Are companies like LinkedIn and New York Times using Node for critical enterprise shit, or simply for a web interface for light stuff like mobile and customer interaction? People like to point to PayPal, but that's only one out of hundreds and thousands of major corporations. As the author says, most of the big shops aren't basing their businesses on Node and JS. They put their trust in real languages like Java, C#, Python, C++ and Scala.